Improvement in millstone-dressers



v V the carbon-point holder.

UNITED" PATENT rrro,nr

JOHN MODONALD MGINTYRE, OF LOCKPORT. NEW YORK, ASSIGNOR OF ONE THIRD HISRIGHT TO WILLIAM DUNCAN, OF SAME PLACE.

IMPROVEMENT IN WllLLSTONE-DRESSERS.

Specification forming part'of Letters Patent No. 92,l79, dated June 19,1877 application tiled April 10. 1877.

To all whom it may concern Be it known that I, JOHN MoDoNALD MGINTYRE,of the city of Lockport, in the county of Niagara and State of New York,have invented certain new and useful Improvements in Millstone-Dressers,which improvements are fully set forth in the followingspeciticatiomreference being had to the accompanying drawing.

My invention relates to an apparatus designed for dressing and furrowingmillstones, and which is so constructed that the carbonpoint `is readilysecured in the tool-stock,`and

. the latter so mounted as to enable the point to operate at anydesiredangle and inclination.

The nature of my invention will be fully understood from the followingdescription.

In the accompanying drawings, consisting of two sheets, Figure 1 is a front elevation of my improved apparatus. Fig. 2 is a rear elevation, andFig. 3 a top-plan view, thereof. Fig. .4 is a cross-section'r in line w,Fig. 3. Fig. 5 is an end view of `the apparatus. Fig. 6 is a detachedview, on an enlarged scale, of Fig. 7 is a lsectional elevation of oneof the feed-screws and connecting parts. Fig. 8 is a top-plan view thereof. Fig. 9 is a detached view of one of the centering-screws.

Like letters of reference designate like parts in each of the igures.

A represents the rectangular bed-frame of the machine, provided-withraised end pieces A', and having arranged at its inner end a bracket, B,in which the centering-screw b works. The bracket B is connected withthe frame A by an angle-piece, B', made laterally adjustable on the endpiece A' of the frame by bolts b1 passing through slotted holes. Thebracket B is `made longitudinally adjustable onthe angle-piece `B' bybolts b2 passing through slotted holes, as shown in Figs. l and 2. Thesetwo adjustments at'rightangles to each other enable the position of thecentering-screw b to be so regulated that the position of the frame Aconforms with the draft of the furrow to be operated upon.

The end pieces A of the frame are each provided on their inner side witha curved recess or bearing, O, having'the form of a circular arc, asshown in Fig. 5; D is a block, of corresponding form, fitted into eachof the recesses C, so as to readily `turn therein, and adjustablysecured to the end pieces A' by one or more bolts, d, passing throughcurved slots d1, as shown in Fig. '5; Each of the blocks D is providedon its inner side with parallel guides d2, so arranged that they will behorizontal when the blocks are in their normal position, as shown inFig. 4. E represents a longitudinal bar arranged between the two blocksD D, so as to slide with its ends between the guards d2 thereof. F Frepresent the two longitudinal guide-bars of the tool-stock, arranged,respectively, on the upper and lower side of the bar E, and rigidlyconnected together at the front thereof by a plate F', so as to form achannel or U-beam, as clearly shown in Fig. 4. The outer faces of thebars F F are madeconvex or roofshaped, so as to properly hold thetool-stock.

The guide-barsFF are secured to the bar E near its outer end by apivot-bolt, f, and near its inner end by a bolt, f', passing through aslotted hole in the bar E, and into the backplate F', so as to enablethe inner ends of the bars F Fto be adjusted vertically on the bar E. `gis a vertical set-screw, Working in the bar .E near its inner end, andengaging against both the upper and lower bars F, so that by raising orlowering the screw g the inner ends of the guide-bars F F can be raisedor lowered, the bars turning on the pivot-boltf While being so adjusted.

H H' represent the horizontal feed-screws arranged in the rear of thebar E, and bearing against the same with their inner ends, whilev theirouter ends bear against pieces h secured to the rear side of the bar E,'thereby compelling the latter-to follow the movements of thefeed-screwsin either direction. The feedscrews work through-threaded 'bearings lpiv-v oted to the upper side of a plate, m, which latter is hung at itsforward end by a pivot to a stationary plate, m1, secured to alongitudinal bar, M, which is attached, by means of crosspieces m, tothe segmental blocks D.

The cross-.pieces m2 may, at the same time, form the lower guide-bar d2of said blocks, as shown at Fig. 4.

o o1 o2 are three pulleys mounted ou the outer feed-screw H, and of otwo pulleys secured to the inner feed-screw H'. The first pulley,0, uponthe outer` feed-screw is the feedpulley, by means of which thefeed-screw is turned every time the tool-stock passes over the same inan outward direction, while the other two pulleys, o1 o2, as well as thepulleys o3 o4 upon the screw H', are band-pulleys, designed tocommunicate the motion of the screw H to the screw H', by means of anendless band, o5. The pulleys ol o3 are made of the same size, while thepulley o2 is smaller, and the pulley o4 correspondingly larger, than thepulleys o1 03, so that when the endless band o5 is placed upon the equalpulleys ol o3 both feed-screws will be turned with the same speed,while, when the band is placed upon the unequal pulleys o2 o, the innerfeed-screw H' will be turned slower than the outer screw H, therebychanging the angle of the toolstock guides every time the feed-screwsare turned.

By this means the outer end of the bar E can be moved forward fasterthan the inner end, which movement will cause the bar and the feed-screwmoving` the same to assume a position of more or less inclination towardthe guides al2 and connecting-bar M, which position the feed-screws areenabled to assume by pivoting their bearings l to the pivoted plates m,as above described.

P represents the reciprocating toolstock mounted upon the bars F F, soas to slide thereon, and held in place on the same by one or more keys,p. Q is the clamp in which the carbon-point holder is secured. It isarranged between vertical dovetail ways in the tool-stock P, so as to bereadily raised and lowered by means of a screw, p'.

The carbon-point holder is composed of a hollow sleeve, r, split at itslower end, which latter is conically enlarged, while its upper end isprovided with a screw-shank and nut, r1 r2. S is a tube or hollowcylinder inclosing the sleeve r, and having its lower end beveled, sothat as the nut r2, (which bears against the upper end of the tube S) istightened the enlarged lower end of the. split sleeve 1^ is drawnagainst the end of the tube S, thereby compressing the two jaws of thesplit sleeve 1', and firmly clamping the carbon-point placed between thesame.

The clamp Q is provided with a vertical bore for the reception of theholder S, and, if desired, the cap of the clamp Q may be formed in onepiece therewith, so that it can be closed or released by a single screw,q, the slit severing the cap from the body of the clamp being arrangedonly on one side of the bore of the clamp.

t represents a pawl or-dog arranged on the rear side of the tool-stockP, so as to turn the friction pulley o every time the tool-stock movesover the same outwardly, the pawl striking against a fixed stop, t,during its forward movement, while during the return movement the pawlwill be raised, and ride over the pulley without moving the same.

The centering-screw b (shown in Figs. 1, 2, and 5) is designed to beengaged with the end of the spindle in .dressing the bed stone, or itsend is engaged in the recess of a temporarycenter-piece in dressingstones not yet provided with a spindle or bail. rPhe screw b providedwith a long neck, as shown in Fig. 9, is designed to be engaged with thecenter of the bail in dressing the runner.

By adjusting the bracket B carrying the centering-screw b toward or fromthe guidebars E F of the tool-stock by means of the bolts b1 b2, theposition of the guide-bars F is readily made to conform to the draft ofthe furrows intended to be operated upon. Upon loosening the bolts d thebearing-blocks D D, on which the guide-bar E slides, can be' partiallyturned in their bearings, so as to incline the bars E F and thetool-stock sliding thereon to correspond with the bevel ofthe furrows.

Upon raising or lowering the inner ends of the guide-bars E F of thetool-stock by means of the screw g, the depth of the cut is decreased orincreased toward the eye of the stone, as may be desired.

Having thus fully described my invention, what I'claim as new, anddesire to secure by Letters Patent, is-

l. In a millstone-dresser, the combination, with the frame A andcentering-screw b, of the angle-piece B', made laterally adjustable onthe frame, and bracket or screw-bearing B, made longitudinallyadjustable on the anglepiece, substantially as and for the purpose lhereinbefore set forth.

2. The combination, with the frame A and tool-stock bar E, of the endpieces A', provided with segmental recesses O, and adjustable segmentalblocks D, provided with Ways d2 for adjusting the inclination of thetool, substantially as hereinbefore set forth.

3. The combination, 4with the bar E, of the guide-bars F F F', pivotednear their outer ends to the bar E at f, and made vertically adjustableat their inner ends by the setscrew g and bolt f', passing through theslotted hole in the bar E, substantially as and for the purposehereinbefore set forth.

4. The combination, with the frame A, provided with ways d2, and bar Esliding therein, of the feed-screws H H', provided, respectively, withpulleys o1 o2 and o3 o4, constructed as described, and endless band o5for feeding both ends of the bar E, either with the same speed or withdifferent speeds, substantially as hereinbefore set forth.

5. The combination, with the feed-screws H H and cross-piece M, of thepivoted bearand nut r1 r2, and inclosingcylinder S, sul)- ings l andpivoted plates m, substantially stantially as and for the purposehereinloefore as and for the purpose hereinbefore set forth. set forth.

6. In a millstone-dresser, the combination, JOHN MODONALD MCINTYRE. withthe tool'stoek P, of the carbon-point hold- Witnesses: er composed 0fthe split sleeve 1', provided with JOHN D. PAYNE, a eonieally enlargedlower end, and screw CEAS. H. ASHFQRD.

